The present invention relates to a printer and, more particularly, to a printer having a receipt paper printing mechanism and a journal paper printing mechanism operated in synchronism with each other such as used in an electronic cash register wherein either one of the printing mechanisms can be optionally rendered to be inoperative.
Heretofore, simultaneous printing operation can be easily achieved in both the receipt paper printing mechanism and the journal paper printing mechanism of a printer used in an electronic cash register. However, it is often required in a printer of an electronic cash register to operate only the journal paper printing mechanism while the receipt paper printing mechanism is kept inoperative.
In case a compact electronic table printer is modified so as to be incorporated in an electronic cash register, the paper feeding mchanism and the printing mechanism are integrally constructed as a unit in such a printer so that an additional receipt paper arresting mechanism must be incorporated in the unit in order to satisfy the above requirement. In such a case, however, the printing mechanism for the receipt paper is still operated in synchronism with the printing mechanism for the journal paper so that repeated printing operation is effected on the receipt paper stationarily held by the receipt paper arresting mechanism thereby giving damages to the receipt paper, the ink ribbon and the members relating to the printing operation. In order to avoid the above disadvantages, it is necessary to provide a switch between the control circuit of the printer and the receipt paper printing mechanism for disconnecting the latter from the former when it is desired to render the receipt paper printing operation to be inoperative. Such a switch may be provided separately from the receipt paper arresting mechanism. In this case, however, the manipulation of the cash register is made complicated rendering false function to occur.
The present invention aims at avoiding the above disadvantages.